1. Field of the Invention
The present general inventive concept relates to an image forming apparatus, a motor control apparatus, and a method of controlling a motor, and more particularly to an image forming apparatus, a motor control apparatus, and a method of controlling a motor in which a back electromotive force (EMF) of a direct current (DC) motor may be sensed using a resistor that is connected in series to the DC motor, and in which a voltage that is supplied to the DC motor may be varied in accordance with a driving speed that corresponds to the sensed back EMF.
2. Description of the Related Art
An image forming apparatus is an apparatus which performs generation, printing, reception, and transmission of image data. Representative examples thereof may include a printer, a copy machine, a facsimile, and a multifunction peripheral (MFP) in which the functions of the above-described devices are combined.
In such an image forming apparatus, motors that perform various functions, such as conveyance of print sheets and feeding of print sheets, are used. More recently, with the ability to attach optional units to an image forming apparatus to perform various functions, such as, for example, an Auto Document Feeder (ADF) unit, a finisher unit, a High Capacity Feeder (HCF) unit, and a Double Capacity Feeder (DCF) unit, the number of motors has increased to be useable in an image forming apparatus.
Although various kinds of motors may be used in an image forming apparatus, DC motors are most common. A DC motor is a motor that uses direct current power. In order to drive such a DC motor at a desired speed, it is necessary to generate a voltage command value using speed information acquired by a sensor that detects a rotating speed of the DC motor, and a speed command value of a processor, and to provide a pulse-width modulated (PWM) signal that corresponds to the generated voltage command value to the DC motor.
In order to make the DC motor follow the speed command value, acquisition of the speed information from the sensor is required. Accordingly, a sensor that can sense the speed of the DC motor is required to control the DC motor speed, and a space to mount the sensor therein is also required.